Earlier quoted context omitted.
Damaging high doses can be as little as a few minutes in the Australian summer so I think it's fair to keep that in mind. On your evolution comment, most Australians don't have dark skin, but the ones who were here before Europeans do. I think that is a good indicator that the body is adjusting to something harmful. On the other hand, many dark skinned people in Britain aren't in a climate they evolved for either. We…
Adding some information for those interested in more precise numbers. This paper [1] has the recommended exposure time for a few cities in Australia. If you live in the same latitude, as long you live in the same latitude, this can be used as a guideline. https://staging.mja.com.au/system/files/issues/194_07_040411...
From the table there, for example, in Townsville in summer, with 11% of your body exposed, it takes just 6 minutes to synthesis 1000 IU of vitamin D.
A fair-skinned female friend who studied at James Cook University used to complain she got sunburnt walking between classes... So DWG, if you read this, apologies for telling you off for exaggerating!